Sun unleashes huge solar flare at the end of 11-year cycle

Our Sun may add to the fireworks as our American friends celebrate their  Independence Day

On Monday, July 2, a regiona of our Sun known as active region 1515 unleashed a solar flare aimed squarely at the Earth. This group sunspots – from which solar flares originate — has been crackling with radio and X-ray energy for days and Monday’s flare was an M5.6-class flare, just a notch down from the strongest possible.

While this isn’t all that surprising, it will have some very noticeable effects here on Earth. Our sun goes through 11-year cycles and will near the peak of cycle 24 next year. As we get closer to that peak, flares are going to get more intense. This most-recent flare was only the latest in a string, including an X-class flare which dealt our Earth’s magnetic field a glancing blow on March 7.

Our history is riddled with the effects of solar flares. Solar flares carry intense amounts of energy that can actually add electricity to our phone lines, fiber optic cables and satellites that we use for all of our modern activities. The now-famous Bastille Day event on July 14, 2000, and the X45-class Halloween flare of 2003 caused communications disruptions worldwide around the peak of the last solar cycle. Back in 1989, a flare caused 6 million people in Quebec to lose power when it overloaded transformers.

Historically, one of the largest events was the Carrington Super flare of 1859, which caused the Northern Lights to be seen as far south as Puerto Rico and disrupted telegraph lines around the world. In fact, operators on the east coast of the United States found there was enough current on the line to send telegraph messages even with their batteries disconnected.

But with an aging power infrastructure and a growing reliance on communications technology, there is now some concern as to what a powerful flare would do today. In space, solar activity can damage satellites and endanger astronauts. Passengers flying along polar routes may even experience a substantially higher dose of radiation, forcing some flights to re-route.

That’s why a fleet of international spacecraft are now monitoring the Sun as never before in human history. These include the European Space Agency’s Solar Heliospheric Observatory, the Proba-2  microsattelite, Japan’s Hinode, and NASA’s Solar Dynamics Observatory.

NASA’s Twin STEREO spacecraft also monitor the Sun from different vantage points along Earth’s orbit, giving us a full 360 degree view of the solar surface.

This solar cycle may prove to be lackluster by historic standards. Between 2008 and 2010, scientists recorded the lowest ebb of solar activity in the past century and there is some conjecture that Cycle 25 may be especially weak, following the theories of NASA solar physicist David Hathaway who supposed that the churning behaviour in the Sun’s interior is actually slowing down and the entire solar cycle may be disrupted as soon as 2022.

When this has happened in the past, cosmic ray levels have also gone  up when we’re at a solar minimum. The solar wind ebbs and more particles from beyond our solar system are able to reach the Earth. One famous, and hotly debated, extended solar lull was known as the Maunder Minimum, which stretched from 1645 to 1715. During this period, the Thames River froze, virtually no sunspots were recorded by the observers of the day and crops failed due to short growing seasons.

Unfortunately, a weak solar cycle and cooling via global dimming (albedo or reflectivity due to increased cloud cover) may be masking the effects of global warming, adding fuel to the political debate.

Whatever the case, our sun is worth keeping an eye on. If skies are clear, observers across North America above latitude 40 degree north may be in for a summer showing of the aurora borealis. This is one of nature’s finest spectacles, and requires no equipment—just a set of eyes– to watch.

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Storms From the Sun

Geomagnetic Storms
One of the most common forms of space weather, a geomagnetic storm refers to any time Earth's magnetic environment, the magnetosphere, undergoes sudden and repeated change. This is a time when magnetic fields continually re-align and energy dances quickly from one area to another.

Geomagnetic storms occur when certain types of CMEs connect up with the outside of the magnetosphere for an extended period of time. The solar material in a CME travels with its own set of magnetic fields. If the fields point northward, they align with the magnetosphere's own fields and the energy and particles simply slide around Earth, causing little change. But if the magnetic fields point southward, in the opposite direction of Earth's fields, the effects can be dramatic. The sun's magnetic fields peel back the outermost layers of Earth's fields changing the whole shape of the magnetosphere. This is the initial phase of a geomagnetic storm.

The next phase, the main phase, can last hours to days, as charged particles sweeping into the magnetosphere accumulate more energy and more speed. These particles penetrate closer and closer to the planet. During this phase viewers on Earth may see bright aurora at lower latitudes than usual. The increase – and lower altitude – of radiation can also damage satellites traveling around Earth.

The final stage of a geomagnetic storm lasts a few days as the magnetosphere returns to its original state.

Geomagnetic storms do not always require a CME. Mild storms can also be caused by something called a corotating interaction region (CIR). These intense magnetic regions form when high-speed solar winds overtake slower ones, thus creating complicated patterns of fluctuating magnetic fields. These, too, can interact with the edges of Earth's magnetosphere and create weak to moderate geomagnetic storms.

Geomagnetic storms are measured by ground-based instruments that observe how much the horizontal component of Earth's magnetic field varies. Based on this measurement, the storms are categorized from G1 (minor) to G5 (extreme). In the most extreme cases transformers in power grids may be damaged, spacecraft operation and satellite tracking can be hindered, high frequency radio propagation and satellite navigation systems can be blocked, and auroras may appear much further south than normal.

Solar Radiation Storms
A solar radiation storm, which is also sometimes called a solar energetic particle (SEP) event, is much what it sounds like: an intense inflow of radiation from the sun. Both CME's and solar flares can carry such radiation, made up of protons and other charged particles. The radiation is blocked by the magnetosphere and atmosphere, so cannot reach humans on Earth. Such a storm could, however, harm humans traveling from Earth to the moon or Mars, though it has little to no effect on airplane passengers or astronauts within Earth's magnetosphere. Solar radiation storms can also disturb the regions through which high frequency radio communications travel. Therefore, during a solar radiation storm, airplanes traveling routes near the poles – which cannot use GPS, but rely exclusively on radio communications – may be re-routed.

Solar radiation storms are rated on a scale from S1 (minor) to S5 (extreme), determined by how many very energetic, fast solar particles move through a given space in the atmosphere. At their most extreme, solar radiation storms can cause complete high frequency radio blackouts, damage to electronics, memory and imaging systems on satellites, and radiation poisoning to astronauts outside of Earth's magnetosphere.

Diamond Earrings

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NASA satellite tastes atoms away from the solar system

NASA's Interstellar Boundary Explorer, the centerpiece of a $169 million mission map the boundary of the sun's influence, has detected atoms from interstellar space streaming by Earth, finding the material is dissimilar from the chemical make-up of the solar system, scientists announced Tuesday.

The data recommend the area of interstellar space just outside the solar system may be deficient in oxygen compared to its abundance inside the heliosphere, a teardrop-shaped bubble blown out by the energy from the solar wind. The heliosphere's bubble is compressed ahead of the sun's motion like a bow shock in front of a ship, while it stretches behind the solar system similar to a boat's wake.

The heliosphere blocks most hazardous cosmic radiation from reaching Earth.

Researchers published their results in the Astrophysics Journal on Jan. 31. IBEX found 74 oxygen atoms for every 20 neon atoms in the interstellar material, compared with 111 oxygen atoms for every 20 neon atoms within the solar system.

IBEX, launched in October 2008, uses two instruments to identify energetic neutral atoms as they strike the spacecraft. If the imagers are facing the right direction when the particle meets the satellite, the atom registers and the instrument can distinguish its elemental composition.

IBEX is in an orbit stretching 200,000 miles from Earth, placing the craft outside of the planet's magnetic field, a constraint to detect energetic particles streaming in from the outer heliosphere and interstellar space.

NASA's Hubble Observes Young Dwarf Galaxies Bursting With Stars

Using its near-infrared vision to peer 9 billion years back in time, NASA's Hubble Space Telescope has uncovered an extraordinary population of young dwarf galaxies brimming with star formation. While dwarf galaxies are the most common type of galaxy in the universe, the rapid star-birth observed in these newly found examples may force astronomers to reassess their understanding of the ways in which galaxies form.

The galaxies are a hundred times less massive, on average, than the Milky Way, yet churn out stars at such a furious pace that their stellar content would double in just 10 million years. By comparison, the Milky Way would take a thousand times longer to double its star population.

The universe is estimated to be 13.7 billion years old, and these newly discovered galaxies are extreme even for the young universe -- when most galaxies were forming stars at higher rates than they are today. Astronomers using Hubble's instruments could spot the galaxies because the radiation from young, hot stars has caused the oxygen in the gas surrounding them to light up like a bright neon sign.

"The galaxies have been there all along, but up until recently astronomers have been able only to survey tiny patches of sky at the sensitivities necessary to detect them," said Arjen van der Wel of the Max Planck Institute for Astronomy in Heidelberg, Germany, lead author of a paper on the results being published online on Nov. 14 in The Astrophysical Journal. "We weren't looking specifically for these galaxies, but they stood out because of their unusual colors."

The observations were part of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS), an ambitious three-year study to analyze the most distant galaxies in the universe. CANDELS is the first census of dwarf galaxies at such an early epoch.

"In addition to the images, Hubble has captured spectra that show us the oxygen in a handful of galaxies and confirmed their extreme star-forming nature," said co-author Amber Straughn at NASA's Goddard Space Flight Center in Greenbelt, Md. "Spectra are like fingerprints. They tell us the galaxies' chemical composition."

The resulting observations are somewhat at odds with recent detailed studies of the dwarf galaxies that are orbiting as satellites of the Milky Way.

"Those studies suggest that star formation was a relatively slow process, stretching out over billions of years," explained Harry Ferguson of the Space Telescope Science Institute (STScI) in Baltimore, Md., co-leader of the CANDELS survey. "The CANDELS finding that there were galaxies of roughly the same size forming stars at very rapid rates at early times is forcing us to re-examine what we thought we knew about dwarf galaxy evolution."

The CANDELS team uncovered the 69 young dwarf galaxies in near-infrared images taken with Hubble's Wide Field Camera 3 and Advanced Camera for Surveys.

Diamond stud

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Star Blasts Planet With X-rays

A nearby star is pummeling a companion planet with a barrage of X-rays 100,000 times more intense than the Earth receives from the sun.

New data from NASA's Chandra X-ray Observatory and the European Southern Observatory's Very Large Telescope suggest that high-energy radiation is evaporating about 5 million tons of matter from the planet every second. This result gives insight into the difficult survival path for some planets.

The planet, known as CoRoT-2b, has a mass about three times that of Jupiter -- 1,000 times that of Earth -- and orbits its parent star, CoRoT-2a at a distance roughly 10 times the distance between Earth and the moon.

The CoRoT-2 star and planet -- so named because the French Space Agency’s Convection, Rotation and planetary Transits, or CoRoT, satellite discovered them in 2008 -- is a relatively nearby neighbor of the solar system at a distance of 880 light years.

"This planet is being absolutely fried by its star," said Sebastian Schroeter of the University of Hamburg in Germany. "What may be even stranger is that this planet may be affecting the behavior of the star that is blasting it."

According to optical and X-ray data, the CoRoT-2 system is estimated to be between about 100 million and 300 million years old, meaning that the star is fully formed. The Chandra observations show that CoRoT-2a is a very active star, with bright X-ray emission produced by powerful, turbulent magnetic fields. Such strong activity is usually found in much younger stars.

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Having a Solar Blast

The Sun unleashed an M-2 (medium-sized) solar flare, an S1-class (minor) radiation storm and a spectacular coronal mass ejection (CME) on June 7, 2011 from sunspot complex 1226-1227. The large cloud of particles mushroomed up and fell back down looking as if it covered an area of almost half the solar surface.

The Solar Dynamics Observatory (SDO) observed the flare's peak at 1:41a.m. ET (0641 UT). SDO recorded these images (above) in extreme ultraviolet light that show a very large eruption of cool gas. It is somewhat unique because at many places in the eruption there seems to be even cooler material -- at temperatures less than 80,000 K. All of the solar Heliophysics System Observatory missions captured the event.

When viewed in Solar and Heliospheric Observatory's (SOHO) coronagraphs (top right), the event shows bright plasma and high-energy particles roaring from the Sun.

Also to the right are links to the Solar Terrestrial Relations Observatory (STEREO) Ahead and Behind coronograph videos showing the CME expansion as viewed from each side of the sun. The STEREO Ahead satellite precedes the Earth as it circles the Sun. The STEREO Behind satellite follows behind the Earth in it's orbit of the Sun.

This not-squarely Earth-directed CME is moving at 1400 km/s according to NASA models. The CME should deliver a glancing blow to Earth's magnetic field during the late hours of June 8th or June 9th. High-latitude sky watchers should be alert for auroras when the CME arrives.